Republic of Ireland international Murphy, 29, had been with Scunthorpe for five years and made 227 appearances.

His spell with the club saw two promotions to and two relegations from the Championship and a Johnstone's Paint Trophy final defeat by Luton at Wembley.

Mirfin, 26, joined the Iron three years ago and played 111 times.

Knill continued: "With Joe and David, they more or less came out and said they wouldn't be here next year. We had meetings with both players and they effectively said they were looking to be somewhere else.

"Unfortunately, the ball was in their court and they both decided they wanted to be somewhere else next season.

"I wish them luck, they've done really well in the short time I've been here and I have been really impressed with their attitude."

Neither left-back Coleman nor midfielder Williams made a first-team appearance for the Iron.

Morris, another midfielder, made 92 appearances for the club, but spent last season on loan at Chesterfield. Cowan-Hall, a striker, made a single appearance before spending the last three months of the season on loan at Rushden & Diamonds.